Recently, image display apparatuses for providing three-dimensional images are being developed. Such an image display apparatus displays an image associated with each of the left and right eyes of a viewer based on parallax between the eyes. For example, the viewer can view a three-dimensional image by wearing glasses, i.e., lenses for the right and left eyes of the viewer provided with a filter for selectively transmitting light from the image for the right eye and a filter for selectively transmitting light from the image for the left eye, respectively.
For example, the image for the right eye and the image for the left eye are displayed based on beams of light which are polarized in different directions such that each beam can be selected by either of the above-described filers (for example, see JP-A-2004-109528 (Patent Document 1)).
For example, Patent Document 1 has disclosed the use of two types of linearly polarized light polarized in directions which are 90 degrees different from each other to provide images for the right and left eyes of a viewer separately.
Specifically, light from a liquid crystal panel is converted into linearly polarized light by a polarizer. Next, a part of the linearly polarized light is transmitted through a retardation film to rotate the polarization direction of the light at 90 degrees to provide, for example, light of an image for the right eye. On the contrary, the rest of the linearly polarized light is not transmitted through the retardation film, and the light undergoes no change in the polarization direction thereof, the light being rendered as an image for the left eye. Thus, the viewer is presented with light of an image for the right eye and light of an image for the left eye which are polarized in directions 90 degrees different from each other.
The viewer may view a three-dimensional image by wearing glasses, i.e., a lens for the right eye and a lens for the left eye on which a polarization filter transmitting linearly polarized light for the right eye and a polarization filter transmitting linearly polarized light for the left eye are disposed, respectively.
JP-A-2005-173033 (Patent Document 2) has disclosed the use of such a retardation film (wave plate filter) disposed in the form of a strip in association with every other horizontal line of pixels of a liquid crystal display unit.